Benchmarks suite tool

[p1c2u]

This pull request introduces a major overhaul of the benchmarking tools for the pathable project. The benchmarks are now shipped as a public toolkit within the main package, providing a new CLI (pathable-bench) for running and comparing benchmarks. The old test-based benchmark scripts are deprecated but still available for compatibility. Documentation and CI workflows have been updated to reflect these changes.

The most important changes are:

Benchmark Tooling and CLI:

• Added a new public benchmark toolkit in the pathable.benchmarks package, including a CLI entrypoint (pathable-bench) for running and comparing benchmarks. This CLI supports running parse and lookup scenarios, selecting implementations, and comparing results. [1] [2] [3] [4] [5] [6] [7] [8]

• Introduced implementation resolution logic to allow benchmarking arbitrary BasePath subclasses by dotted path or module:qualname syntax.

Documentation Updates:

• Updated the README.md with new instructions for installing and using the benchmark CLI, including optional extras for benchmark dependencies and highlighting the deprecation of the old test-based scripts.

CI Workflow Updates:

• Modified the GitHub Actions workflow to use the new benchmark CLI modules instead of the old test-based scripts.